The Chase state occurs when the NPC is following and moving towards the player. In Dead Keys, this happens whenever the scene camera moves into a trigger volume or area where zombies are waiting:

Chase state

The following is the Chase coroutine (for the Chase state). It contains some interesting features, considered further in the comments section:

    //------------------------------------ 
    public IEnumerator StateChase() 
    { 
         
 
        //Run chase animation 
        ThisAnimator.SetInteger("AnimState", (int) ActiveState); 
 
        //Set destination 
        ThisAgent.SetDestination (PlayerTransform.position); 
 
        //Wait until path is calculated 
        while (!ThisAgent.hasPath) 
            yield return null; 
 
        //While in chase state 
        while(ActiveState == AISTATE.CHASE) 
        { 
            if (ThisAgent.remainingDistance &lt...